Ancient building material, terra cotta, could help address modern global challenge: the climate crisis

Team Walter P. Moore huddles during an Architectural Ceramic Assemblies Workshop prototyping session in the School of Architecture and Planning’s fabrication shop in Parker Hall. Credit: Douglas Levere/University at Buffalo

“Buildings account for two-thirds of final energy use and more than half of the world’s greenhouse gases. Yet the materials and assembly methods used for building facades have remained essentially the same since the 1950s. ”

Omar Khan

associate professor and chair of architecture at UB

BUFFALO, N.Y. — Architects have turned to terra cotta for millennia. The clay-based ceramic is durable, lasting hundreds of years; it breathes, providing a natural system to transfer heat and water; and its sculptural qualities turn buildings into intricate and colorful works of art.

University at Buffalo researchers are exploring how to combine these age-old properties into design solutions for one of today’s most pressing global challenges: the climate crisis.

Now in its second year, the Architectural Ceramic Assemblies Workshop (ACAW) convened architects, engineers and ceramicists from around the world in Buffalo in August to develop terra cotta façade prototypes with a focus on bioclimatic, or environmentally-responsive design.

The resulting projects range from a facade-integrated, terra cotta radiator that transfers ambient heat into and throughout buildings to ribboned terra cotta panels that apply efficient digital fabrication methods and support evaporative cooling.

Omar Khan, associate professor and chair of architecture at UB and a workshop co-organizer, says the goal is to bring innovation into an arena that is still lagging behind despite available technologies.

“Buildings account for two-thirds of final energy use and more than half of the world’s greenhouse gases. Yet the materials and assembly methods used for building facades have remained essentially the same since the 1950s,” he says. “The skin of architecture must adapt to and mitigate such changes in our environment. Bioclimatic design invites us to change the paradigm from disposability to longevity.”

ACAW was launched in 2016 by Boston Valley Terra Cotta, the School of Architecture and Planning; UB’s Sustainable Manufacturing and Advanced Robotic Technologies (SMART) Community of Excellence; and Alfred University’s College of Ceramics to create a collaborative forum for experimental research and development with architectural terra cotta.

John Krouse, president of Boston Valley Terra Cotta, says the workshop is part of a long-term vision with UB and Alfred University to create a residency program in architectural terra cotta based in Buffalo. “We’re combining the models of academic research, artistic experimentation, and industry expertise to generate ceramic façade solutions for today’s biggest architectural challenges.”

Advancing design concepts from the inaugural workshop in 2016, four research teams consisting of industry leaders, researchers and students developed their prototypes over the course of a four-day workshop, which was part maker faire and part academic conference.

The teams presented their work at a public forum at the conclusion of the conference in August, at the Hotel Henry in Buffalo. The four groups are expected to advance results into full-scale projects, patented products and actual buildings.

The projects are:

Team UB/Alfred — Performative ornament

A system of terra cotta shingles developed by Team UB/Alfred. Credit: Laura Garófalo.

Developing a system of terra cotta shingles and a thermally active screen. Team UB/Alfred explored the material’s bioclimatic and ornamental possibilities through dynamic configurations and innovation in glazing techniques. Fired with a textured opalescent glaze, the shingle surface both plays with light and air and supports passive cooling. The layered shingles channel water and light while keeping heat away from the building through channels across the panels. Similarly the reconfigurable screen works as both a trombe wall and shading device, alternatively collecting and reflecting solar heat gain through rotation of the components.

The team focused on digital techniques, specifically digital sculpting, and CNC (computer numerical control) mold-making for slip cansting. A customized script, developed with the support of students, can generate thermally responsive arrays of the shingles.

A colorful, articulated terra cotta exterior collects and transfers heat to a custom-designed terra cotta radiator system on the interior. Featuring a complex network of piping, the “counter-current” heat exchanger evenly channels heat throughout the building with little to no energy use.

By reducing the typical peaks and valleys of energy consumption associated with conventional building facades, the system essentially camouflages the building to the climate. The team took its cues from nature, including turkey vultures that spread their wings to stay cool and cacti that maintain heat through ribbed bodies.

The components were designed to take advantage of the forming techniques and the thermal capacity of terra cotta to optimize energy exchange. The team also explored press-mold fabrication methods and the integration of supportive valve, plumbing and control systems.

Known world-wide for its canopied building systems, New York City-based design and structural engineering firm Walter P. Moore investigated a post-tensioned system of terra cotta panels that could be combined into larger, full-scale assemblies.

Looking to flip the geometry and create an airiness with the dense material, the team explored composite formulations and assembly methods to enhance the material’s structural possibilities. Research questions included how terra cotta’s structural properties can improve by adding carbon, glass and organic fibers, and cellular structural formations; environmental performance through heating and cooling systems, insulation, thermal mass and ventilation; and the integration of media, fiber optics and integrated lighting.

The Los Angeles-based design firm Morphosis explored façade applications for a commissioned project that is currently in the design phase. Looking to push the limits of Boston Valley’s tooling capabilities, the team focused on hand-packed and digitally-driven extrusion methods with rain screen terra cotta.

Their goal is to create a façade system with kinetic effects, both bioclimatically and aesthetically. Its assembly of ribboned terra cotta panels would create the perception of movement while also supporting natural ventilation and evaporative cooling through a cavernous central atrium.

Omar Khan says the format of the intensive, hands on charrette, along with continuous research engagement throughout the year, is as innovative as the products it generates. “We’re forming a new model of working, outside traditional realms of practice.”

Mitchell Bring, a researcher with Boston Valley Terra Cotta, who worked closely with Khan and UB architecture professor Laura Garofalo to design the workshop, says the goal was to flatten the process of design research, bringing all parties and stages into one event. “Here, everyone participates in solving the problem.”

The experience is an invaluable real-world learning experience for students, adds Khan. He and Garofalo recruited 10 students to work alongside the four teams. Throughout the workshop, students could be seen huddled with the practitioner leads, trouble-shooting design and assembling the prototypes using UB’s expansive fabrication shop.

“We came into this fresh and are now helping the teams lay out different design orientations,” says Quincy Koczka, a Master of Architecture student and assistant to the Walter P. Moore team. “It’s exciting and a different challenge.

For practitioners, it’s a ready-made forum for practice innovation.

Stan Su, director of Morphosis, says he couldn’t pass up the opportunity to work with UB’s architecture program and the nation’s leading manufacturer of architectural terra cotta. “We are interested in expanding our knowledge of materials – their fabrication methods and bioclimatic potential. This workshop serves as a sort of test bed for materials research. In a way it was self-interest. We were grateful for the opportunity.”

Erik Verboon, co-founder and managing director of Water P. Moore’s New York office, says the forum provides much-needed space for proof-of-concept research for ideas that might otherwise be dismissed as too complex. “We were developing a design that required cable running in three directions. We thought, ‘this can’t be done.’ But over the course of the workshop, Boston Valley validated that it can be done. We didn’t know until we got here.”

Plans are in the works for next year’s workshop to be held in the newly renovated SMART factory space in Parker Hall. Issues that the invited teams will address include unitization of façade systems, creative use of new digital techniques and tools, the performative capacity of glazing and other issues pertaining to bioclimatic design.